Sn=A1(1-Rn) over 1-r using formula 1-2+4-8+........-a10

Question

geometric series

Answer 1

S_n = a(1 - rⁿ) / (1 - r) is the formula for the sum of "n" terms of a geometric series.

a = first term, r= common ratio, n = number of terms, S_n = sum of "n" terms

 

S₁₀ = 1(1 - (-2)¹⁰) / (1 - (-2))

S₁₀ = (1 - 1024) / 3

S₁₀ = -1023 / 3

S₁₀ = -341